External Morphology of Larvae of Belgica antarctica Jacobs, 1900 (Diptera, Chironomidae) Obtained from Two Locations in Maritime Antarctica

Abstract

The external morphology of the fourth-instar larva of the Antarctic endemic chironomid midge Belgica antarctica is described. Larvae were collected from Jougla Point (Wiencke Island) and an un-named island close to Enterprise Island, off the coast of the western Antarctic Peninsula. Light microscopy was used to examine and document photographically the structures of the mouthparts (mandible, mentum, premandible, labrum), antennae, pecten epipharyngis, clypeus, frontal apotome and posterior parapods. Measurements of the mouthparts are presented. The data obtained are compared with that available in the literature. A number of differences were identified relating to the size of the larvae, the number of teeth on the mandibles, the number of antennal segments and the length of the antennal blade. Malformations of the mandible and mentum are reported for the first time in this species. Features of larvae of taxonomic value that can be used to determine the species in larval stages are presented. These are of utility in using the larvae to reveal relationships with other species. Larvae are also important in ecological and genotoxicological studies, which require accurate species level identification.

Unsupervised learning for detection of possible sexual dimorphism in larvae of Belgica antarctica Jacobs (Diptera, Chironomidae)

“…In recent years, this midge has been studied actively in numerous research on its genomic, phylogenetic, physiological, biochemical, ecological, and life cycle features (e.g., Benoit et al 2009, Allegrucci et al 2012, Harada et al 2014, Kelley et al 2014, Kawarasaki et al 2019, Finch et al 2020, Potts et al 2020, Ajayi et al 2021, Michailova et al 2021a, Spacht et al 2021, Yoshida et al 2021). In addition, recently, Michailova et al (2021b) described the external morphology of the 4 th instar larvae of this species.…”